diff --git a/SmalllestPositiveMissingNumber.cpp b/SmalllestPositiveMissingNumber.cpp
new file mode 100644
index 0000000..2064023
--- /dev/null
+++ b/SmalllestPositiveMissingNumber.cpp
@@ -0,0 +1,36 @@
+#include <iostream>
+using namespace std;
+
+int main()
+{
+
+    int n;
+    cin >> n;
+    int arr[n];
+    int N = 1e6 + 2;
+
+    bool check[N] = {0};
+
+    for (int i = 0; i < n; i++)
+    {
+        cin >> arr[i];
+        if (arr[i] >= 0)
+        {
+            check[arr[i]] = 1;
+        }
+    }
+
+    int ans = -1;
+    for (int i = 0; i < N; i++)
+    {
+        if (check[i] == 0)
+        {
+            ans = i;
+            break;
+        }
+    }
+
+    cout << ans << endl;
+
+    return 0;
+}